Re: Unique Ice Dam over Sunroom - Please Help!
My guess is that the leak is at the junction of the metal roof and the house. The metal roof is fairly flat. I am guessing that the snow melts faster on the asphalt roof and runs down on a frozen metal roof. The water backs up under the shingles and down behind the metal drip edge. Also in the one picture it looks like the junction is poorly caulked.
I would first seal the junction with roofing tar going at least half way up the drip edge, then seal the bottom of the asphalt shingles to the roof, and keep the metal roof cleared of snow.
If that doesn't work get someone in to do a proper installation.
Be sure you live your life, because you are a long time dead.-Scottish Proverb